People performing manual watchmaking tasks often work with their hands at eye level, and occupy raised work stations, where their forearms are in a substantially horizontal position. Despite this particular arrangement, such people are often subject to musculoskeletal problems, particularly epicondylitis affecting the wrist, elbow or shoulder, and spinal problems, in addition to fatigue which is difficult to measure.
CH Patent 248542 in the name of MEYER & STUEDELI describes a workbench with forearm supports which, in a top view, form an obtuse angle with each other, and are each tilted in a vertical plane, and project from the workbench towards the user so that he does not have to lean forward.
FR Patent 1400357 in the name of SORMEL describes a workbench with symmetrical forearm support surfaces each tilted in a vertical plane, on either side of a horizontal platform forming a substantially trapezoid work surface, with which the forearm supports form a continuous smooth surface, covered with suitable coatings, on the one hand on the forearm surfaces, and on the other on the work surface. There are known improvements to this type of workbench with forearm supports that are each tiltably adjustable in a vertical plane by means of a connecting rod assembly.
CH Patent 394989 and CH Patent 512971 in the name of G.E. SCHLUP & Co. disclose this type of work stations with ball and socket point forearm supports.
US Patent 2014/020985 in the name of DesRoches discloses an automated workstation with some automated degrees of freedom, notably with a work surface that is height adjustable or completely movable on a circular rail.
However, these arrangements are insufficient for workers who are permanently required to work with their elbows resting on a support surface, and with their back resting against the back of a chair, and these benches do not include means for prevention of ankylosis and musculoskeletal problems.